Michael Arrington rates Skype one of his most important work and social tools but the way people use it is driving him crazy, hence this primer on appropriate Skype etiquette. "It’s not a conversation until both sides are engaged. Just because I haven’t blocked you on Skype doesn’t mean that you have an open door into my brain. The best way to start a Skype conversation is to message something like 'are you free?' If I respond then we’re all set. If not, don’t take it personally. And don’t start firing off whatever you want to say anyway."